/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.flink.table.runtime.operators.bundle;

import org.apache.flink.api.java.functions.KeySelector;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.streaming.runtime.streamrecord.StreamRecord;
import org.apache.flink.streaming.util.OneInputStreamOperatorTestHarness;
import org.apache.flink.table.runtime.operators.bundle.trigger.CountBundleTrigger;
import org.apache.flink.util.Collector;

import org.junit.jupiter.api.Test;

import javax.annotation.Nullable;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;

import static org.assertj.core.api.Assertions.assertThat;

/** Tests for {@link MapBundleOperator}. */
class MapBundleOperatorTest {

    @Test
    void testSimple() throws Exception {
        @SuppressWarnings("unchecked")
        TestMapBundleFunction func = new TestMapBundleFunction();
        CountBundleTrigger<Tuple2<String, String>> trigger = new CountBundleTrigger<>(3);
        KeySelector<Tuple2<String, String>, String> keySelector =
                (KeySelector<Tuple2<String, String>, String>) value -> value.f0;

        OneInputStreamOperatorTestHarness<Tuple2<String, String>, String> op =
                new OneInputStreamOperatorTestHarness<>(
                        new MapBundleOperator<>(func, trigger, keySelector));
        op.open();
        synchronized (op.getCheckpointLock()) {
            StreamRecord<Tuple2<String, String>> input = new StreamRecord<>(null);

            input.replace(new Tuple2<>("k1", "v1"));
            op.processElement(input);

            input.replace(new Tuple2<>("k1", "v2"));
            op.processElement(input);

            assertThat(func.getFinishCount()).isEqualTo(0);

            input.replace(new Tuple2<>("k2", "v3"));
            op.processElement(input);

            assertThat(func.getFinishCount()).isEqualTo(1);
            assertThat(Arrays.asList("k1=v1,v2", "k2=v3")).isEqualTo(func.getOutputs());

            input.replace(new Tuple2<>("k3", "v4"));
            op.processElement(input);

            input.replace(new Tuple2<>("k4", "v5"));
            op.processElement(input);

            assertThat(func.getFinishCount()).isEqualTo(1);

            op.close();
            assertThat(func.getFinishCount()).isEqualTo(2);
            assertThat(Arrays.asList("k3=v4", "k4=v5")).isEqualTo(func.getOutputs());
        }
    }

    private static class TestMapBundleFunction
            extends MapBundleFunction<String, String, Tuple2<String, String>, String> {

        private int finishCount = 0;
        private List<String> outputs = new ArrayList<>();

        @Override
        public String addInput(@Nullable String value, Tuple2<String, String> input)
                throws Exception {
            if (value == null) {
                return input.f1;
            } else {
                return value + "," + input.f1;
            }
        }

        @Override
        public void finishBundle(Map<String, String> buffer, Collector<String> out)
                throws Exception {
            finishCount++;
            outputs.clear();
            for (Map.Entry<String, String> entry : buffer.entrySet()) {
                outputs.add(entry.getKey() + "=" + entry.getValue());
            }
        }

        int getFinishCount() {
            return finishCount;
        }

        List<String> getOutputs() {
            return outputs;
        }
    }
}
